River discharge measured with continuous water level measurements converted by a stage-discharge relation based on manual discharge measurements. 15 min sample values in m3/s. The hydrometric station is located ~2.5 km upstream of where the Zackenberg river enters the fjord. After 2014, water level in the river is measured by sensors logging the vertical distance from the bridge down to the water surface, backed up by pressure sensors in the river. The time series starts in 1996. Before 2014, water level was measured by a distance sensor mounted on a gallows rack on the river bank, supported by pressure sensors in the water. The station was moved once because of bad snow conditions, and was also exposed to floods, in some years this resulted in downtimes for the station and subsequent gaps in the timeseries (see timeseries comments in the metadata text file for details). Nearly every year, a glacier lake outburst flood (GLOF) is released from the A.P. Olsen glacier which lies in the northwestern corner of the river catchment. Several of these GLOFs have modified the river bed to a large degree, and a new stage-discharge relation has had to be established afterwards. The discharge measured during the GLOF period is subject to larger uncertainties than other periods due to high water levels and changing bed conditions. Zackenberg river freezes in Autumn and has no flow through winter, except in rare years when the GLOF happens during the winter months. The spring flow runs on top of the winter ice until the channel has melted down to the river bed, and the river stage in this period needs to be corrected for the influence of the ice in order to calculate correct discharge. Ice affected periods at both the start and the end of the season are corrected for by ice correction factors based on manual discharge measurements. For years when manual discharge measurements could not be made, data for the ice-affected periods are excluded from the time series. Years where this has not been done are given in the metadata. Please read the metadata file provided with the data for comments related to the data in this timeseries.
